Is this the face of Father Christmas?

Ask anyone over the age of three to describe Santa Claus and the result will be an almost universal depiction of a portly, ruddy-faced, genial, old gentleman with a long white beard and a penchant for scarlet.

This image has been passed down from generation to generation and stares out at us from millions of Christmas cards and advertising campaigns each year.

But if the pioneering work of British and Italian scientists is to be believed, the patron saint of children, the man who fills our stockings and brings festive cheer by the sackload, is an altogether less amiable-looking fellow.

According to Caroline Wilkinson, an anthropologist at Manchester University who has created the remarkable three- dimensional image seen here, Saint Nicholas - the 4th-century Turkish saint who has morphed over the years into Father Christmas - was something of a bruiser.

Although he was slimmer than popular myth dictates, he sported olive skin, a crew cut, a sharply-trimmed grey beard and a broken nose - derived, it is said, from a physical altercation with a bishop. For all his benevolence Saint Nicholas, it seems, was not averse to stating his point forcefully.

'If you saw this man in your living-room on Christmas Eve you'd get the shotgun out,' says Anand Kapoor, a member of the research team that constructed the remarkable three-dimensional image of Saint Nicholas seen here.

The astonishing new take on an ancient visage has been painstakingly pieced together by Italian forensic pathologist Professor Francesco Introna and his associates using modern diagnostic methods and computer technology.

It casts a fascinating new slant on a story that is part legend, part religious history.

Born in AD 270 in the town of Patara (now part of southern Turkey), Nicholas was orphaned at an early age by the plague. A devout Christian growing up in a land that was then entirely under Roman rule, he was routinely persecuted.

Fortunately, he had inherited vast wealth. But instead of using his riches to protect himself against his Roman oppressors, Nicholas gave generously to the poor.

One of the most famous stories about him involves Nicholas saving three impoverished sisters from shame, by paying their dowries for them and thus enabling them to marry.

According to the tale, the girls' father was so poor he could not provide for them and their only means of survival would have been to go into prostitution.

Then what seemed to the family to be nothing short of a miracle occurred. For three consecutive nights a bag of gold sailed in through the poor man's window - enough to enable all three girls to marry.

On the third night their grateful father lay awake to see who was being so generous to his family. When he saw Nicholas deposit the money, he broadcast the godly man's beneficence to anyone who would listen.

As word spread of his charitable works, Nicholas was embraced by the Christian Church. On moving to nearby Myra, he was made a bishop and continued to bestow gifts on the poor.

One account details how he saved an entire town from starvation.

In another he is said to have saved three innocent men who were about to be beheaded in AD 313. He is said to have heard about the execution and dashed across town, arriving just in time to dash the sword from the executioner's hand.

Other tales credit him with bringing three children back to life and resurrecting the daughter of his landlady who had fallen into a fire and been burnt to ash.

He died either in 345 or 352, aged around 70, and whatever the truth of these accounts they were deemed sufficient to have him declared a saint, shortly afterwards.

He was buried in Myra and the kudos attached to his relics brought the town commercial wealth - not least because his bones apparently oozed an oily liquid that enterprising locals sold as 'manna' for curing disease.

But while Myra profited, other towns and cities grew jealous. Possession of a saint's relics was the key to a thriving local economy - Venice boasted the bones of St Mark - and a source of much envy.

'In the late Middle Ages, saints were seen as more than just people who should be remembered and imitated,' says the Rev Alister McGrath, professor of historical theology at Oxford University.

'They were seen as people who could help you in the Christian life in many ways. Some believed that possessing the relics of a saint would get you to Heaven faster than other people.'

And so it was that in early May 1087, some 750 years after St Nicholas's death, a commando of 63 Italian mercenaries and sailors from the Southern Italian port of Bari smuggled themselves into the Byzantine harbour town of Myra, intent on securing the relics for themselves.

In a bloody battle they smashed their way into the dead man's shrine, stole his bones and returned triumphantly to Bari on May 6 - a date still celebrated throughout Italy today as the feast of St Nicholas.

His relics have remained there ever since, in the Basilica di San Nicola, and turned Bari into a thriving port and tourist destination.

The only time his tomb has ever been opened was in the 1950s when repairs to the crypt were made and they had to be moved to allow workmen in. shed new light on some of the myths that have grown up around the industry of Santa Claus.

The modern-day custom of a generous benefactor bestowing gifts on children at Christmas time began in the 12th century when a group of French nuns, inspired by the saint's largesse, delivered stockings packed with nuts and oranges to the homes of the poor, on the Eve of St Nicholas's day, December 6.

The idea was embraced across Europe and by the 16th century had become widespread. Dutch settlers took the legend with them to the U.S. where the transformation began from 4thcentury Turkish benefactor to modern- day icon of consumerism.

A drawing in 1860 for Harper's Weekly first depicted St Nicholas sporting a beard, a pipe and a waistcoat and the snappy new moniker 'Santa Claus'.

Twenty years later the first sighting of a red coat on a Christmas card was recorded, and by 1931 this image was imprinted upon the psyche of the Western world by a Coca-Cola advertisement that ran for 30 years.

Now modern profilers are wondering if Rudolph the rednosed reindeer was in some way derived from the broken nose of St Nicholas.

And at last the curious nature of pawn-brokers' and perfumiers' interest in the saint - he is patron of both industries - can also be explained.

The pawn-brokers' symbol of three gold balls is apparently derived from the three bags of gold St Nicholas left for the three dowry-less sisters, while perfumiers were attracted to the saint because the 'manna' which oozed from his bones was said to be sweet-smelling.

None of these facts, however, will hold much truck with today's children. Their interest in Santa Claus remains, as it has always been, with his amazing ability to deliver the gifts they most want, to all the children of the world, simultaneously.

And no broken nose or menacing haircut will alter that.